1. Field of Invention
The invention relates generally to recycling of asphalt shingles, and in particular, to a system and method for recycling of asphalt shingles utilizing heat treatment.
2. Description of Art
Asphalt concrete pavement is commonly used in roadway construction. The asphalt concrete pavement typically comprises liquid asphalt cement combined with aggregate. The aggregate is usually a mixture of sand, gravel, and stone. The aggregate and liquid asphalt cement are mixed and heated to form an asphalt paving composition. The crushed gravel and stone particles of the aggregate provide sharp edges which, when combined with the liquid asphalt cement, create an aggregate interlock which improves the strength of the composition.
Liquid asphalt cement can be expensive. Shredded asphalt roofing shingles are often used as a substitute for liquid asphalt cement. The asphalt roofing shingles are sometimes “recycled” and incorporated into the asphalt pavement composition.
It is difficult to regulate the consistency of the asphalt pavement composition produced by existing recycling processes. Also, air emissions from existing recycling processes can be detrimental to the atmosphere.